The present invention relates to an apparatus and a method of recognizing vehicles travelling behind.
Recent vehicles are excellent on quietness and sound insulation, so that it is hard for drivers to hear external sounds. If it is a warning sound from an emergency vehicle such as a police car and an ambulance travelling behind, the emergency vehicle could be obstructed by the vehicle travelling ahead due to quietness and sound insulation.
Japanese Unexamined-Patent Publication No. 10-214399 discloses a method of detecting an emergency vehicle travelling close behind and providing the information to drivers by using information offered from special detecting equipment installed on roads.
Moreover, Japanese Unexamined-patent Publication No. 11-306494 discloses a method of detecting an emergency vehicle travelling close behind and providing the information to drivers by using information obtained by in-vehicle camera and microphone equipment.
The former method is, however, disadvantageous in that an emergency vehicle travelling close behind is detected only on roads on which the detecting equipment is installed.
The latter method can be applied on any road but is disadvantageous in that it is hard for drivers to recognize what type of emergency vehicle is travelling close behind, making it difficult to decide what evasive action to take.
A purpose of the present invention is to provide an apparatus and a method of recognizing vehicles travelling behind, that give effective information to drivers on what type of vehicle is travelling close behind so that drivers can take an appropriate evasive action, thus contributing to a safe and smooth traffic flow.
The present invention provides an apparatus for recognizing a vehicle travelling behind including: a detector for detecting images of objects existing behind a first vehicle in which the apparatus is installed to obtain distance data on the objects in relation to the first vehicle, thus recognizing one of the objects as a second vehicle travelling behind the first vehicle based on the distance data; a first determining unit for determining the type of the second vehicle in size based on the images; and a second determining unit for determining whether the second vehicle is an emergency vehicle based on the images.
Moreover, the present invention provides a method of recognizing a vehicle travelling behind including the steps of: detecting images of objects existing behind a first vehicle to obtain distance data on the objects in relation to the first vehicle, thus recognizing one of the objects as a second vehicle travelling behind the first vehicle based on the distance data; determining the type of the second vehicle in size based on the images; and determining unit for determining whether the second vehicle is an emergency vehicle based on the images.